Ex-F1 driver Alex Zanardi underwent a third operation in Italy and remains in intensive care following the hand bike accident suffered by the racer last month.
Zanardi sustained serious head and facial injuries that required two neurological operations by surgeons at the Siena University Hospital.
The two-time CART driver and Paralympic gold medalist returned to the operating room on Monday for a five-hour operation that focused on facial reconstruction.
"The patient has undergone a new surgery, performed by the professionals of the maxillofacial and neurosurgery, aimed at cranio-facial reconstruction and stabilisation of the areas affected by the trauma," read the latest health bulletin from Zanardi's doctors.
"The fractures were complex," said Professor Paolo Gennaro, director of the hospital's maxillofacial surgery unit.
"This required careful programming that made use of computerised, digital and three-dimensional technologies, made to measure of the patient.
"The complexity of the case was rather singular, even if it is a type of fracture that we routinely face in our centre."
Zanardi remains in a medically induced coma in the Siena University Hospital's intensive care unit.
"His condition remains stable from the cardio-respiratory and metabolic point of view, [and] severe from the neurological point of view," the bulletin concluded.
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